A multitude of construction methods and materials are available for the construction of fences and retaining walls. Common fence constructions include wood picket, stockade, chain length, concrete or stone columns with wood pickets spanning between the columns, and stone/brick fences, to name a few. Retaining walls are typically made of stone or brick, and may include reinforcement by incorporation of geotextile sheets.
Recently, segmental concrete retaining wall units that are dry stacked have become a popular product for the construction of retaining walls. Because the units are dry stacked, they are built without the use of mortar that reduces the cost of construction since the services of a stone mason are not required, as well as savings realized in material costs. Without the use of mortar, retaining walls must incorporate some feature that interlocks and aligns the individual block units.
One reference disclosing a mortarless retaining wall block and retaining wall system includes U.S. Pat. No. 6,615,561. This reference specifically discloses a retaining wall block having a core opening, pin receiving cavities, and pinholes. The pin receiving cavities and pinholes are arranged on the blocks symmetrically and substantially interior of the block corners thus resulting in a more structurally stable block yet permitting optimal alignment of the block cores when constructing a retaining wall. The cores may be filled with mortar or aggregate to increase the strength of the wall system.
Another example of a reference disclosing a retaining wall block is the U.S. Pat. No. 5,551,809. This reference also discloses retaining wall blocks including a core, pin receiving cavities, and pinholes. However, the arrangement of the pinholes and pin receiving cavities is such that each successive row is set back from a lower row to form a slope angle of between about 30–75°.
Another reference disclosing a wall block in a retaining wall construction is the U.S. Pat. No. 5,865,006. In this reference, the wall block includes a removable flange having pin apertures that pass through the flange and into the body of the block. This type of block allows construction of walls having flange connections between adjacent courses of blocks or, when the flange is removed, pin connections between adjacent courses of blocks.
The U.S. Pat. No. 6,447,213 discloses yet another type of retaining wall system wherein blocks have different face sizes. The blocks in this reference may also incorporate pins for interconnecting courses of blocks. The faces have varying sizes based on variations in width. These variations in width allow the retaining wall system to be built in a multitude of different linear or angular arrangements. Each block also has at least three faces that are textured to produce the appearance of natural stone.
U.S. Pat. No. 4,996,813 discloses a wall block especially adapted for use in reinforced concrete wall systems to produce a sound barrier. The front end of the block has a protruding bullet shaped nose. A rear end of the block has a cavity shaped to receive the bullet shaped nose of an adjacent block. Blocks can be vertically stacked, or may be staggered with respect to one another to provide offset courses of blocks. Pins are used to interconnect courses of blocks.
The construction of modular concrete retaining walls as disclosed in the above prior art references includes a few simple steps. First, a leveling pad of dense base material or non-reinforced concrete is placed, compacted and leveled. Next, the initial course of blocks is placed and leveled. For systems that utilize pins, the pins are then placed in each block in the designated pinholes. Next, a core fill material such as crushed rock aggregate is placed in the cores of the blocks and other spaces between the blocks to add mass and strength to the wall structure for strength, as well as to encourage drainage through the retaining wall. Succeeding courses of blocks are then placed in a pattern according to the design of the particular blocks. For example, succeeding courses of blocks may be placed in a pattern such that each block to be placed is located between the two blocks directly below it. Pin receiving cavities of the bottom blocks are configured to align with pinholes of the succeeding upper blocks thereby facilitating a pinned connection between upper and lower courses of blocks.
Although segmental block construction is well known for retaining walls, it is less common for construction of fences. Many housing developments include a perimeter fence that delineates the boundaries of the particular development. Because of the cost of placing conventional brick fences or decorative stone fences, perimeter fences surrounding a development are typically made of much less costly materials such as wood pickets. However, particularly in wetter climates, wood picket fences quickly deteriorate, and must be replaced frequently. When a fence begins to deteriorate, it reflects poorly on the quality and overall reputation of the particular development. As metropolitan areas continue to grow, traffic noise has created problems for many suburban neighborhoods that were once fairly remote and not subjected to high traffic noise. Wood fences are inadequate structures for creating a sound barrier.
Therefore, there is a need for an economical fence system having the attributes of a retaining wall in terms of permanency and strength, yet the fence system being especially adapted in a fence construction to include use of various block types to accommodate the number of required turns in a standard fence layout. Accordingly, the fence provided should be a permanent solution for perimeter fences, or any other locations that demand a more permanent solution to standard fence constructions. Additionally, there is a need for an economical fence construction that can reduce undesirable traffic noise.